JPS5840935B2 - Highly selective production method of chlorinated phenoxytoluenes - Google Patents

Description

Detailed Description of the Invention The present invention provides highly selective chlorination of chlorinated phenoxytoluenes represented by phenoxybenzyl chlorides or phenoxybenzal chlorides by selectively chlorinating the methyl side chain of phenoxytoluenes. It relates to a manufacturing method.

The chlorides obtained here are easily converted into phenoxybenzyl alcohols and phenoxybenzaldehydes, respectively, by hydrolysis, but among these, m-phenoxybenzyl alcohol and m-phenoxybenzaldehyde are important as agricultural chemicals (insecticides). It is an intermediate raw material.

Although various methods for synthesizing phenoxybenzyl alcohols or phenoxybenzaldehydes have been reported, the best method that can be implemented industrially has not yet been established.

Regarding the methyl side chain chlorination method of phenoxytoluenes, which is considered to be one type of industrially advantageous synthesis method, the following patents have already been filed in the past.

1, Japanese Patent Publication No. 51-45573, West German Patent No. 2402457; A method is disclosed in which m-phenoxytoluene is directly chlorinated using a halogen in a high temperature range of 220° C. or higher.

This method is industrially disadvantageous because it involves reaction operations at high temperatures and consumes a large amount of energy.
It is.

Moreover, this method has been shown to remove a large amount of nuclear chloride when the reaction temperature is lower than 220°C.

2, JP-A-53-40732, US Pat. No. 4,108,904; Chlorination of m-phenoxytoluene is carried out in carbon tetrachloride using sulfuryl chloride or chlorine and bromine as halogenating agents.

However, it has been shown to use a radical initiator for reactions using sulfuryl chloride, and a powerful incandescent light source for reactions using chlorine and bromine.

It has been shown that this method suppresses nuclear chlorination and causes side chain chlorination.

3, JP-A-53-46929, US Pat. No. 4,146,737; A side chain chlorination method using sulfuryl chloride as a halogenating agent in m-phenoxytoluene in carbon tetrachloride in the presence of a radical initiator is disclosed.

4. Japanese Patent Publication No. 53-10.3433, West German Patent Application No. P
2707232.8; A method of side chain chlorination of m-phenoxytoluenes in hydrogen tetrachloride using UV light and chlorine or bromine as a halogenating agent is shown.

5. Japanese Patent Publication No. 53-112824, French Patent Application No. 77
-06941; m-phenoxytoluene in hydrogen tetrachloride in the presence of a radical initiator using N-chloroacetamide, N-bromoacetamide, N-chlorosuccinimide, N-7''romsuccinimide, chlorine or bromine as a halogenating agent. A side chain chlorination method is shown.

However, reactions using sulfuryl chloride, N-chloroacetamide, N-bromoacetamide, N-chlorosuccinimide, N-bromsuccinimide, or bromine as halogenating agents, or methods using light, are not economical when carried out industrially. There are many problems that need to be solved, such as disadvantages and heterogeneity of the reaction system.

On the other hand, the method using chlorine and a radical reaction initiator is easy to operate and economically advantageous; Example 1.2.3 and JP-A-53
The yield of m-phenoxybenzyl chloride and m-phenoxybenzal chloride shown in Example 4) of -112824 is at most 60 to 70% even under optimal conditions.
The selectivity is not high, at only a few percent, and this value is still not industrially satisfactory.

In view of this situation, the present inventors have conducted extensive research and found that one of the phosphorus-containing compounds or oxygen-containing compounds that can form a charge transfer complex with chlorine, chlorine radicals, or organic halogen compounds in the presence of a radical reaction initiator. We have discovered that when phenoxytoluenes are chlorinated with chlorine in the presence of species or mixtures, the methyl side chains are highly selectively chlorinated.

Moreover, it is noteworthy that by selecting the reaction conditions in the present invention, phenoxybenzyl chlorides or phenoxybenzyl chlorides can be further It has been found that the process can be achieved with extremely high yield and high selectivity.

This is a completely new method that cannot be found in conventionally known techniques, and is an economical invention that can be easily implemented industrially.

It is generally known that in the chlorination of aromatic compounds, nuclear substitution by electrophilic reactions and side chain substitution by radical reactions proceed competitively.

This also occurs in the chlorination of +'3 phenoxytoluenes; for example, it has been shown in Japanese Patent Publication No. 45573/1987 that a large amount of nuclear substitution occurs at the same time as side chain substitution.

On the other hand, although it has been shown that ring substitution can be suppressed by using a radical initiator or light in carbon tetrachloride, as mentioned above, the conversion of m-phenoxybenzyl chloride or m-phenoxybenzyl chloride The rate was not completely satisfactory.

Further, as the chlorination of the methyl side chain progresses, phenoxyphenyltrichloromethanes are produced from phenoxybenzal chlorides.

Therefore, in order to produce phenoxybenzal chlorides with high yield and high selectivity, it is necessary to suppress not only nuclear chlorination but also the production of trichlorides, but there are no methods for suppressing these. It has not been reported even in known literature.

Therefore, the present inventors investigated various conditions under which the methyl side chain chlorination of phenoxytoluenes proceeds with high selectivity while suppressing nuclear chlorination and the formation of phenoxyphenyltrichloromethanes, and as a result, the present invention was developed. Reached.

That is, the feature of the present invention is that by coexisting in the reaction system a phosphorus-containing compound or an oxygen-containing compound capable of forming a charge transfer complex with chlorine, a chlorine radical, or an organic halogen compound, chlorine can be removed from the methyl side chain of phenoxytoluenes by chlorine. This method allows the chemical reaction to proceed more selectively and at the same time suppresses the removal of phenoxyphenyltrichloromethanes by insects.

As a result of quantifying the products obtained from this reaction system by gas chromatography and NMR, the present inventors found that phenoxybenzyl chlorides or phenoxybenzal chlorides can be obtained almost quantitatively.

Moreover, at this time, we succeeded in reducing the amount of by-products of phenoxyphenyltrichloromethanes to 5% or less.

In the substituents R1 and R2 of the compound of general formula (I) which is the starting material of the present invention, preferable examples of halogen are chlorine, bromine, etc., preferable examples of alkyl group are methyl, ethyl, butyl, etc. Preferred examples of the alkyl group include chloromethylfuromoethyl, chloropropyl, etc., preferred examples of the acyl group and acyloxy group include acetyl, propionyl, benzoyl, toluoyl, and their corresponding acyloxy groups, and preferred examples of the aryl group. Examples include phenyl, tolyl, xylyl, etc.
Preferred examples of aralkyl groups and aralkyloxy groups include benzyl, phenethyl, phenylpropyl, and their corresponding aralkyloxy groups, and preferred examples of alkoxy groups include methoxy, ethoxy, butoxy, etc.
Preferred examples of the alkoxycarbonyl group include methoxycarbonyl and butoxycarbonyl.

Representative examples of the compound of general formula (I) include o-phenoxytoluene, m-phenoxytoluene, p-phenoxytoluene, 3-phenoxy6-chlorotoluene,
m-bodimethyldiphenyl ether, m-(m-chloromethylphenoxy)toluene, m-(p-pensoylphenoxy)toluene, m-(p-cyanophenoxy)
Toluene, m-(p-nitrophenoxy)toluene, m
(p-phenylphenoxy)toluene, m(p-benzylphenoxy)toluene, m-(p-benzyloxyphenoxy)toluene, p(m-)lyloxy)phenylbenzoate, m(p-methoxyphenoxy)toluene, m(p- -meth)oxycarbonylphenoxy)toluene and the like.

The amount of carbon tetrachloride used in the present invention is in the range of equivalent to 20 times the weight of the phenoxytoluenes,
Preferably it is in the range of 5 to 10 times the amount.

The phosphorus-containing compounds used in the present invention are compounds represented by general formulas (IV) and (V) [wherein W, X and Y may be the same or different, and halogen (chlorine and bromine)] , R3, zR3, NR3R
'(R3 and R4 may be the same or different and each represents hydrogen or an alkyl group having 1 to 20 carbon atoms, an aryl group, an amino group, an alicyclic ring, and a heterocyclic ring with or without a substituent.) and hydrogen (however, in this case, W, X
and Y are the above-mentioned organic groups other than hydrogen), 2 is atomic oxygen or sulfur, and W, X or X and Y are fused together to form an alicyclic ring and a heterocyclic ring. For example, tri-n-butylphosphine, tri-n-octylphosphine, tri-n-dodecylphosphine, n-octadecyldiphenylphosphine, triphenylphosphine, 1-mercaftethyldiphenylphosphine, tricyclohexylphosphine, dicyclohexyl 4 -chlorophenylphosphine, triisopropylphosphine sulfide, n-hexadecyldiphenylphosphine sulfide, triphenylphosphine oxyto, )'J-
n-dodecylphosphine oxide, N-N diethylhydrazinodiphenylphosphine oxide, ■-phenyl 1
-Phosphacyclohexane, n-octadecyldiphenylphosphite, dicyclohexylchlorophosphite, di-n-octylphosphite, diphenylcyclohexylphosphite, triphenylphosphite, tricyclohexylphosphite, diisopropylchlorothiophosphite, tricyclophosphite xylthiophosphite, tri-n-dodecylthiophosphite, triphenylthiophosphite, tris(dimethylamino)phosphine, phosphorustripiperididephosphine, tris(di-n-butylamino)phosphine, phosphorustri(N
-methylanide), diphenylphosphinic chloride, cyclohexylphenylphosphinothioic chloride, di-n-butylphosphinothioic acid, isopropyl n
-hexylphosphinic acid, dicyclohexylphosphinodithioic acid, methyl n-octyl n-hexylphosphinate, O-methyldiisopropylphosphinothioate, phenyldiethylphosphinodithioate, methyldicyclohexylphosphinate, hexamethylenephosphinate Holic triamide, phenylphosphonas dichloride, cyclohexylphosphonic dichloride, S-S diethylphenylphosphonodithioate, diethyl-n-butylphosphonate, 0-O-diethylphenylphosphonotioate, 0.S-diethylphenylphosphonothioate A type or mixture of phosphorus-containing compounds represented by ester, S-ethyl N-N-diethyl P-methylphosphonamidothioate, 〇-ethylphenylphosphonodithioate, 〇-ethyl S-phenyl phenylphosphonodithioate, etc. be.

Further, oxygen-containing compounds include general formulas (VI), (■) and (■
) Compound R5-0-R6 (Vl), R5-OH (■) L ((R7-0napR8-ZzaR7-M]kI
J (■) [In the formula, R5 and R6 may be the same or different (
, each represents an alkyl group having 1 to 20 carbon atoms, an aryl group, an alicyclic ring, and a heterocyclic ring with or without a substituent, and R
5, R6 may be condensed with each other to form an alicyclic, heterocyclic or macrocyclic polyether, R7 and R8 may be the same or different, each is a lower alkylene group, and L is , atomic oxygen or sulfur, and an alkoxyl group having 1 to 20 carbon atoms, an alkylamino group, an alkylamido group, each with or without a substituent,
It represents an aryloxy group, an oxyalicyclic ring, and an oxyheterocyclic ring, and M is hydrogen, halogen (chlorine and bromine), hydroxyl group, mercapto group, or an alkyl group having 1 to 20 carbon atoms, each with or without a substituent, an alkyl carboxyl group and an alkylamino group, further 2 represents atomic oxygen and sulfur, and i is 1 to 50
, j is 0 to 25, k is 2 when L is atomic oxygen or sulfur, and l to 6 in other cases (however, if the formula (Vl
) Compounds having a boiling point of 70° C. or less in the ethers are excluded)] Examples of the oxyalicyclic ring and oxyheterocycle mentioned above include cyclohexyloxy, pyridyloxy, and quinolyloxy.

For example, 2,2'-dichlorodiethyl ether, di-n
-butyl ether, di-n-octyl ether, di-n
-Octadecyl ether, diphenyl ether, naphthyl ethyl ether, dicyclohexyl ether, 4-pyridylethyl ether, p-dioxane, furan, tetrahydrofuran, 15-crown-5, dibenzo-18
-Crown 6, inbutyl alcohol, n-octyl alcohol, n-tetradecyl alcohol, n-oftatecyl alcohol, m-cresol, 2-(3tolyloxy)-3-methylphenol, 2,6-di-t-butyl -4-methylphenol, 2,2/-methylenebis(4
-methoxy-6-t-butylphenol), 4,4'-
Thiobis(3-methyl 6-t-butylphenol), 4
-Hydroxyethyln, cyclohexyl alcohol, ethylene glycol, thiodiglycol, ethylene glycol mono-n-butyl ether, diethylene glycol mono-n-dodecyl ether, propylene glycol diisopropionate, tripropylene glycol monostearate, ethylene Glycol monophenyl ether, β-cyclodextrin, 1,5-sorbitan monostearate, glycerin monopalmitite, bis(hydroxyethylthioethyl) ether, bis(mercaptoethylthioethyl) ether, bis(chloroethoxyethyl) ether, Bis(aminoethylthioethyl) ether, thiodiglycol hexamer, polyethylene glycol (average molecular weight 1000), polypropylene glycol (average molecular weight 3000), polyoxydiethylene glycol 5
-Sorbitan monostearate (average molecular weight 1000)
, polyoxyethylene glycerin monopalmitite (average molecular weight so o ), polyoxyethylene dodecyl ether (average molecular weight 800), polyoxyethylene tododecyl phenyl ether (average molecular weight 700), polyoxyethylene laurylamine (average molecular weight 600) ,
Polyoxyethylene laurylamide (average molecular weight 500
) or a mixture of oxygen-containing compounds.

These phosphorus-containing compounds and oxygen-containing compounds are 0.001 to 50% by weight, preferably 0.001 to 50% by weight based on the phenoxytoluenes.
．． 01-30% by weight is used.

When the amount added is 50% by weight or more, the desired reaction may hardly proceed, and when the amount added is 0.001% by weight or less, almost no effect is observed.

The radical reaction initiator used is an azo compound or peroxide, preferably azobisisobutyronitrile or benzoyl peroxide, and the amount used is 0.001 to 20% by weight based on the phenoxytoluenes. , preferably 0.01 to 15% by weight.

Chlorine used in the reaction is blown into the reaction system at a rate of 0.5 to 10 mol %, preferably 2 to 5 mol %, of the phenoxytoluene per minute until the reaction is sufficiently completed.

On the other hand, the reaction temperature is in the range of 0 to 150°C, preferably at a temperature at which the reaction system gently refluxes.

The present invention will be explained in more detail with reference to Examples below.

Example 1 ★ m phenoxytoluene 95? as phenoxytoluenes in a flask equipped with a thermometer, stirrer, gas inlet tube, and reflux condenser tube. (0.52 mol), 10 g of azobisisobutyronitrile as a radical reaction initiator, 11 g of triphenylphosphine as a phosphorus-containing compound, and 1300 f of carbon tetrachloride as an organic halogen compound, and the internal temperature of the flask was set to 78 ~
The temperature is raised to a range of 82°C and the system is brought to gentle reflux.

This was reacted for 75 minutes while blowing 0.023 mol/min of chlorine into the flask from the gas inlet tube.

After the reaction was completed, the flask was cooled, and carbon tetrachloride was distilled off under reduced pressure to obtain a pale yellow product.

As a result of gas chromatographic analysis of this product, the yield was 4.9% m-phenoxybenzyl chloride, m-
Phenoxybenzal chloride 90.1%, m-phenoxyphenyltrichloromethane 4.2%, nuclear substitute 0.8%
Met.

As a comparative example, when triphenylphosphine was not added, the yields of the reaction products obtained under the same conditions were: 41.0% of m-phenoxytoluene, 45.7% of m-phenoxybenzyl chloride, and 45.7% of m-phenoxybenzyl chloride. Chloride 1
2.1% and nuclear substitutes 1.2%.

Examples 2 to 15 Table 1 shows the yields of reaction products obtained when typical phenoxytoluenes were used instead of m-phenoxytoluenation in the same manner as in Example 1.

Examples 16 to 125 Reaction products obtained when m-phenoxytoluene is used as the phenoxytoluene and a typical phosphorus-containing compound or oxygen-containing compound is added to the reaction system in the same manner as in Example 1. The yield of the product is shown in Table 2.

Examples 126 to 127 Reactions obtained when the phenoxytoluenes shown in Table 3 were used instead of m-phenoxytoluene as the starting material by the same operation as in Example 1. show.

Claims (1)

[Scope of Claims] 1 General Formula (I) [In the formula, R1 and R2 may be the same or different and each represents hydrogen, halogen, an alkyl group, a halogenoalkyl group,
represents an acyl group, an acyloxy group, a cyano group, a nitro group, an aryl group, an aralkyl group, an aralkyloxy group, an alkoxy group, or an alkoxycarbonyl group. , X and Y may be the same or different,
Halogen, R3, zR3, NR3R' (R3 and R4
may be the same or different, and each represents hydrogen or an alkyl group having 1 to 20 carbon atoms, an aryl group, an amino group, an alicyclic ring, or a heterocyclic ring with or without a substituent. In this case, two of W, X and Y are the above-mentioned organic groups other than hydrogen, and 2 is atomic oxygen or sulfur, and W, may form a ring or a heterocycle] and/or (b) formula (%) [wherein R5 and R6 are the same or different, R represents an alkyl group, an aryl group, an alicyclic ring, or a heterocyclic ring having 1 to 20 carbon atoms, each with or without a substituent;
5, R6 may be condensed with each other to form an alicyclic, heterocyclic or macrocyclic polyether, R7 and R8 may be the same or different, each is a lower alkylene group, and L is , represents atomic oxygen, sulfur, or an alkoxy group, alkylamino group, alkylamido group, aryloxy group, oxyalicyclic group, or oxyheterocyclic group having 1 to 20 carbon atoms, each with or without a substituent, and M is , hydrogen, halogen, hydroxyl group, mercapto group, or a carbon number of 1 with or without a substituent, respectively
~20 alkyl group, carboxylalkyl group or alkylamino group, further Z represents atomic C oxygen or sulfur, i is 1 to 50, j is 0 to 25, k is L is atomic oxygen or 2 for sulfur, 1 to 6 for other cases (however, boiling point 70°C in ethers of formula R5-0-R6)
The following compounds are excluded: General formula (n) or (III), characterized in that it is selectively chlorinated by R1 and R
2 has the same characteristics as those described above. 2 The compound (■) is 0-phenoxytoluene, m-phenoxytoluene, p-phenoxy)/l/ene, 3-
Phenoxy-6-chlorotoluene, m-rd-dimethyldiphenyl ether, m-(m-chloromethylphenoxy)toluene, m-(p-pensoylphenoxy)toluene, m-(p-cyanophenoxy)toluene, m-
(p-nitrophenoxy)toluene, m-(p-phenylphenoxy)toluene, m-(p-benzylphenoxy)toluene, m-(p-benzyloxyphenoxy)
Toluene, p-(m-tolyloxy)phenylbenzoate, m-(p-methoxyphenoxy)toluene, m-
The method according to claim 1, wherein (p-methoxycarbonylphenoxy)-toluene is used. 3. The method according to any one of claims 1 to 2, wherein the radical reaction initiator is selected from an azo compound and a peroxide. 4. The method according to claim 3, wherein the radical reaction initiator is azobisisobutyronitrile or benzoyl peroxide. 5. The method according to any one of claims 1 to 4, wherein the reaction is carried out at a temperature in the range of 0 to 150°C.